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Author
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Topic: What would a transitional fossil look like?
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RAZD
Member (Idle past 1426 days) Posts: 20714 From: the other end of the sidewalk Joined: 03-14-2004
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Message 214 of 403 (850886)
04-16-2019 10:30 AM
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Reply to: Message 194 by Faith
04-15-2019 3:07 PM
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Fun Thought Experiment for Faith
As for some trilobites rolling up I'll have to think about that but offhand it doesn't suggest more than some difference in the way the appendages are arranged, or whatever they are called. The fact that they all have that same overall shape means structure versus a less fixed sort of characteristic. I just can't look at all those various trilobites without putting them in the same class, even the ones where they look like they've unraveled as it were, because they still have that same basic arramgnement of parts. vs the exact same argument re dogs and cats:
As for cats being more flexible than dogs I'll have to think about that but offhand it doesn't suggest more than some difference in the way the appendages are arranged, or whatever they are called. The fact that they all have that same overall shape means structure versus a less fixed sort of characteristic. I just can't look at all those various dogs and cats without putting them in the same class, even the ones where they look like they've unraveled as it were, because they still have that same basic arramgnement of parts. I note that you changed from trilobites all being one species to all being one class ... in your ever evolving position. This is why we think your criteria are not consistently applied nor adequate to explain your position. Also by your argument above, horses, donkeys and zebras are more similar than trilobites. Enjoy Edited by RAZD, : . Edited by RAZD, : ..
| This message is a reply to: | | | Message 194 by Faith, posted 04-15-2019 3:07 PM | | Faith has not replied |
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RAZD
Member (Idle past 1426 days) Posts: 20714 From: the other end of the sidewalk Joined: 03-14-2004
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Message 215 of 403 (850889)
04-16-2019 12:06 PM
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Reply to: Message 194 by Faith
04-15-2019 3:07 PM
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Another Fun Thought Experiment for Faith
Continuing from Message 214 ...
... Yes genes make proteins but particular alleles make particular proteins that form particular traits. Are you going to argue with that? If HOX genes make an arm in one creature but a flipper in another I'm not sure why you'd want to make a big deal out of that. Aside from the erroneous description of how HOX genes work, lets look at the same simplistic criteria of "structural" differences you have delineated for trilobites vs cats and dogs, but instead compare the "structural" differences in DNA between donkeys vs horses and then between humans vs chimps:
quote:
Donkeys vs. Horses: Differences & Similarities Chromosomes Donkeys and horses differ on a genetic level: horses have 64 chromosomes and donkeys have 62. When a horse is bred with a donkey to produce a mule (male donkey, female horse) or a hinny (male horse, female donkey), the offspring have 63 chromosomes. Because of their parents' incompatible chromosomes, these creatures are generally sterile. So if you try to breed two mules with each other, you're not going to have much luck.
Now we look at humans and chimps:
quote:
Chimpanzee genome project Starting the chimpanzee genome project Human and chimpanzee chromosomes are very similar. The primary difference is that humans have one fewer pair of chromosomes than do other great apes. Humans have 23 pairs of chromosomes and other great apes have 24 pairs of chromosomes. In the human evolutionary lineage, two ancestral ape chromosomes fused at their telomeres, producing human chromosome 2.[3] ...
Genes of the chromosome 2 fusion site The results of the chimpanzee genome project suggest that when ancestral chromosomes 2A and 2B fused to produce human chromosome 2, no genes were lost from the fused ends of 2A and 2B. ...
So based on the (simplistic) criteria of the "structural" differences of chromosome numbers, humans are more similar (more closely related) to chimps than donkeys are to horses. Especially when further investigation shows that human chromosome 2 compares structurally to combined chimp chromosomes 2A and 2B, with evidence of fusing remaining in the chromosome 2. Additionally, when we look at the fusion site (above ref continued):
quote:
The results of the chimpanzee genome project suggest that when ancestral chromosomes 2A and 2B fused to produce human chromosome 2, no genes were lost from the fused ends of 2A and 2B. At the site of fusion, there are approximately 150,000 base pairs of sequence not found in chimpanzee chromosomes 2A and 2B. Additional linked copies of the PGML/FOXD/CBWD genes exist elsewhere in the human genome, particularly near the p end of chromosome 9. This suggests that a copy of these genes may have been added to the end of the ancestral 2A or 2B prior to the fusion event. ...
Diagramatic representation of the location of the fusion site of chromosomes 2A and 2B and the genes inserted at this location.
These fusions and the rearrangement of these genes are rather obvious mutations, as the added genetic material was existing in other chromosome structures, so this should not be a problem for your view on new "species that are varieties not species using existing DNA" argument. And I have no problem with these evidence based conclusions ... perhaps you should think about it. Enjoy Edited by RAZD, : .
| This message is a reply to: | | | Message 194 by Faith, posted 04-15-2019 3:07 PM | | Faith has not replied |
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RAZD
Member (Idle past 1426 days) Posts: 20714 From: the other end of the sidewalk Joined: 03-14-2004
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Message 217 of 403 (850899)
04-16-2019 4:01 PM
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Reply to: Message 156 by Faith
04-14-2019 12:21 PM
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Trilobite Thought Experiment for Faith
Well, as long as the three lobes are arranged as they are in all the trilobites, yes. Oh look, I found a bunch of modern trilobites for Faith:
quote:
Augochlora Sweat Bee (Augochlora pura) Ant, Bee, and Wasp Anatomy 1 Antennae: Ants and Bees both have a pair of antennae on the head that senses their surroundings.
2 Head: The head contains the insect's compound eyes, antennae, and mandibles.
3 Thorax: Contains various vital parts such as the aorta and nervous system.
4 Abdomen: Contains various organs including the heart, gut, venom glands, and anus.
5 Legs: Ants and Bees have three pairs of legs attached to the thorax (center-body section).
Where 2, 3, and 4 are the unmistakable 3 lobes arranged as they are in all the trilobites and the primal characteristic of all trilobites ... Gosh this really overturns centuries of scientific thought. Enjoy
| This message is a reply to: | | | Message 156 by Faith, posted 04-14-2019 12:21 PM | | Faith has not replied |
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RAZD
Member (Idle past 1426 days) Posts: 20714 From: the other end of the sidewalk Joined: 03-14-2004
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Re: Trilobite Thought Experiment for Faith
I have been thinking about trilobites since "The Lumper*" led us down this rabbit hole. ... * Among taxonomists there are are sometimes 2 groups, the lumpers and the splitters. The splitters often describe individual species based on a very narrow variation of features, sometime single features and the lumpers tend to disregard narrow variation in features and lump various related populations as a single species. I am not aware of anyone lumping together a whole taxonomic class of organisms like trilobites. ... Except when it comes to human/chimpanzee relationships, then she becomes the consummate splitter: the different lengths of bones become criteria for lack of relationship. Such fun Enjoy
| Replies to this message: | | | Message 227 by Tanypteryx, posted 04-17-2019 3:33 PM | | RAZD has seen this message but not replied |
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RAZD
Member (Idle past 1426 days) Posts: 20714 From: the other end of the sidewalk Joined: 03-14-2004
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Transitionals are intermediate in form/features/time/location from before and after
Hi Mike,
I am not sure if you want an answer to the question, "what would a transitional fossil look like." Call me silly but it seems you would be implying that if one is qualified that we can then affirm the notion that it actually was one, which would seem like an extremely basic error in reason from my perspective. Yes, it is okay to "qualify" what a transitional may look like, the problem is presented in the question, "does that therefore mean it certainly was one?" To answer that question you have to look at the big picture. Criteria is simple:
- are the form and features intermediate between those of an ancestor population/s and descendant population/s?
- are the time/age of the fossil intermediate between those of an ancestor population/s and descendant population/s?
- are the locations of the fossil intermediate between those of an ancestor population/s and descendant population/s?
For instance, Pelycodus:
quote:
Evolution of Pelycodus
an early Eocene Primate from Big Horn Basin, Wyoming
The chart documents the evolution of the Eocene lemur-like primate Pelycodus into Notharctus. The horizontal scale is an index of molar tooth size. Each horizontal bar gives the mean (vertical bar), two standard deviations (thick horizontal bar) and range (thin horizontal bar) for the indicated number of skulls from a series of fossil deposits. The index increase from 1.0 to 1.4 is an approximate doubling in size. The inset photograph shows a reconstruction of Notharctus venticolis, the species in the upper right of the series. [diagram after Gingerich]
Text material © 2005 by Steven M. Carr
Comparing the data from one level to the ones above and below:
- are the form and features intermediate between those of an ancestor population/s and descendant population/s?
Yes: the major difference shown by the fossils is size, increasing over time.
- are the time of the fossil intermediate between those of an ancestor population/s and descendant population/s?
Yes: the fossils are in layers that show time by depth, the deeper the fossil the older it is.
- are the locations of the fossil intermediate between those of an ancestor population/s and descendant population/s?
Yes: all these fossils are from Big Horn Basin, Wyoming.
Ergo each layer is intermediate between ancestor population/s and descendant population/s. Ergo they are transitional fossils. QED. BTW, that's several hundred transitional fossils in that diagram ...
You see your problem is, mathematics alone can prove we can find things that look like transitionals in any designed things as long as there are enough of them. Problems with the design (or progressive creation) hypothesis: (1) it does not explain how the design is actualized, what is the mechanism of design? (2) it does not explain the nested hierarchy of development (why cars don't qualify) (3) but most important, it does not explain the distribution in the temporal/spatial matrix, why there and not elsewhere/elsewhen? The Theory of Evolution does -- remember that the purpose of a theory in science is to explain all the evidence. Enjoy Edited by RAZD, : .
| Replies to this message: | | | Message 241 by Faith, posted 04-18-2019 12:41 PM | | RAZD has replied |
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RAZD
Member (Idle past 1426 days) Posts: 20714 From: the other end of the sidewalk Joined: 03-14-2004
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Message 250 of 403 (851001)
04-18-2019 1:34 PM
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Reply to: Message 241 by Faith
04-18-2019 12:41 PM
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Re: Transitionals are intermediate in form/features/time/location from before and after
More funny stuff from Faith:
That Pelycodus thing is such a joke, RAZD, it's nothing but where the creature and its various relatives, children and cousins were buried in the Flood. Curiously there is no evidence of a major mountain topping flood in the Big Horn Basin, Wyoming, just lots of little annual floods limited to the river flood plain. Just like everywhere else in the world, now and in the past. A single flood does not explain the changes between layers. The Theory of Evolution does explain their location and timing and the gradual transition in form over time ... ALL the evidence. As noted in The Right Side of the News, Message 1295 you have a cognitive bias problem:
quote:
It's called Cognitive bias:
quote:
Cognitive biases are systematic patterns of deviation from norm or rationality in judgment, and are often studied in psychology and behavioral economics.[1] Although the reality of these biases is confirmed by replicable research,[2][3] there are often controversies about how to classify these biases or how to explain them.[4] Some are effects of information-processing rules (i.e., mental shortcuts), called heuristics, that the brain uses to produce decisions or judgments. Biases have a variety of forms and appear as cognitive ("cold") bias, such as mental noise,[5] or motivational ("hot") bias, such as when beliefs are distorted by wishful thinking. Both effects can be present at the same time.[6][7] There are also controversies over some of these biases as to whether they count as useless or irrational, or whether they result in useful attitudes or behavior. For example, when getting to know others, people tend to ask leading questions which seem biased towards confirming their assumptions about the person. However, this kind of confirmation bias has also been argued to be an example of social skill: a way to establish a connection with the other person.[8] Although this research overwhelmingly involves human subjects, some findings that demonstrate bias have been found in non-human animals as well. For example, hyperbolic discounting has been observed in rats, pigeons, and monkeys.[9]
Particularly:
quote:
| Bias blind spot
| The tendency to see oneself as less biased than other people, or to be able to identify more cognitive biases in others than in oneself.[25]
| | Confirmation bias
| The tendency to search for, interpret, focus on and remember information in a way that confirms one's preconceptions.[27]
| | Dunning-Kruger effect
| The tendency for unskilled individuals to overestimate their own ability and the tendency for experts to underestimate their own ability.[41]
| | Focusing effect
| The tendency to place too much importance on one aspect of an event.[46]
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More at (wiki) Cognitive bias.
Thank you for your detailed response. Enjoy
| This message is a reply to: | | | Message 241 by Faith, posted 04-18-2019 12:41 PM | | Faith has replied |
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RAZD
Member (Idle past 1426 days) Posts: 20714 From: the other end of the sidewalk Joined: 03-14-2004
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Message 270 of 403 (851038)
04-18-2019 2:50 PM
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Reply to: Message 269 by Taq
04-18-2019 2:44 PM
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There are multiple violations of your proposed hierarchy. For example, there are models of light trucks and cars that share the same engine while two cars from the same model have different engines. Automobiles do not fit into a nested hierarchy. Then there are SUVs that combine truck frame and engine (and so evade car engine emissions restrictions) with car cabs ... Enjoy
| This message is a reply to: | | | Message 269 by Taq, posted 04-18-2019 2:44 PM | | Taq has not replied |
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RAZD
Member (Idle past 1426 days) Posts: 20714 From: the other end of the sidewalk Joined: 03-14-2004
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Re: Transitionals are intermediate in form/features/time/location from before and after
No offence meant to you Sir, as I wouldn't mean this in a negative way RAZD but this does seem to be a little bit ignorant of creation geology explanations. There really is in modern times a growing list of evidence which is better explained as coming from a mage catastrophe. In fact the record itself is expected from a flood, especially with 100 million years worth of flat gaps in place in many locations, where there is no erosion at the contact points. In other words there are many areas where there is no Cambrian, or no pre-cambrian. With a flood if the rock was laid down by depositions, a series of them, we would expect this because the rock would not be an "era" but a deposit. I don't want to get into this too much but there is the B.E.D.S model which a flood explains better, as well as paraconformities. Also recent experiments on bloat-and-float fossils indicate that local floods wouldn't be sufficient to counter the buoyancy from depositional gases in large critters. It would seem absurd to say that such a huge hydraulic force would not leave giant sediment hauls. It also explains many strange geomorphological features such as water-gaps and planation. Erosional remnants are also well explained given a famous one we know happened because of an ice-age flood. (steamboat inselberg) Huge remnants such as devil's tower tend to change in their explanations and timing. We also have the rates of erosion which just don't match millions of years. I am not intending to elephant-hurl this all at you, I just think that if you are going to give a fairly quick argument/summary, for "not a flood" it's also fair for me to summarise. The problems with the creationist "explanation" for a world wide mountain topping flood are many fold, not least is the problem of timing -- there is no evidence of a single one time flood everywhere around the world and pole to pole. It's the temporal/spatial matrix again. The same problem creationists have with intermediate/transitional fossil "explanations" like design and progressive creation. But an IDologist shouldn't be concerned with biblical stories, unless of course it is just a dodge ... Enjoy
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RAZD
Member (Idle past 1426 days) Posts: 20714 From: the other end of the sidewalk Joined: 03-14-2004
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Message 334 of 403 (851247)
04-21-2019 1:26 PM
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Reply to: Message 321 by Faith
04-21-2019 12:17 AM
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It makes the trilobite one Kind ??? Lolling on the floor
It makes the trilobite one Kind ... This is your main impetus: to create a fictional " kind" that appears nowhere in the bible (or other religious documents), for the sole purpose of making a frivolous line of argument based purely on your ego and your insistence on keeping each "kind" crammed into one "species" ... which in your usage bears no relationship to the scientific biological definitions of species. The fact that the same criteria you use to force this argument can be applied with equal validity to other families of plants, animals, and other organisms is ignored as bias. Keep the comedy rolling. Enjoy
| This message is a reply to: | | | Message 321 by Faith, posted 04-21-2019 12:17 AM | | Faith has replied |
| Replies to this message: | | | Message 335 by Faith, posted 04-21-2019 1:51 PM | | RAZD has replied |
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RAZD
Member (Idle past 1426 days) Posts: 20714 From: the other end of the sidewalk Joined: 03-14-2004
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Message 342 of 403 (851265)
04-21-2019 2:27 PM
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Reply to: Message 335 by Faith
04-21-2019 1:51 PM
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Re: It makes the trilobite one Kind ??? Lolling on the floor
Yes, one species or one Kind, that's how I see all those trilobites climbing up the fossil record for the supposed hundreds of millions of years represented there, and it is the sameness of their body structure that enables me to classify them that way. And where did I call it bias to classify other creatures the same way: The problem you have is that you refuse and ignore classifying other creatures the same way:
... the Kind or species is identified by the body structure. ... Then dogs and cats are a "Kind or species (faith usage)" and chimps and humans a "Kind or species (faith usage)" ... where "species (faith usage)" means some original fantasy "species genome" and NOT species as used in biology, science, reality. So funny to watch you wiggle around the actual evidence. Enjoy
| This message is a reply to: | | | Message 335 by Faith, posted 04-21-2019 1:51 PM | | Faith has replied |
| Replies to this message: | | | Message 366 by Faith, posted 04-22-2019 3:50 PM | | RAZD has replied |
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RAZD
Member (Idle past 1426 days) Posts: 20714 From: the other end of the sidewalk Joined: 03-14-2004
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Message 388 of 403 (851378)
04-23-2019 7:45 AM
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Reply to: Message 371 by Faith
04-22-2019 4:11 PM
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funny definitions make discussion a farce
I don't care what you've "seen," the definitions I gave are my definitions. As usual this "discussion" has become a farce. Nevertheless for a while I will resist the impulse to leave this popstand and go on Inactive because the stupidities and misrepresentations do keep temping me back. And it is your fault that the discussion has become a farce -- you have made it so with your loose and variable "definitions" that defy reason, evidence and consistency. This is the result of your misusing words with known consistent standard definitions to mean something else that is neither standard nor consistent. See Definitions, Daffynitions, Delusions, Logic and Critical Thinking. for further discussion on the need to use proper definitions of technical terms. Enjoy
| This message is a reply to: | | | Message 371 by Faith, posted 04-22-2019 4:11 PM | | Faith has not replied |
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RAZD
Member (Idle past 1426 days) Posts: 20714 From: the other end of the sidewalk Joined: 03-14-2004
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Message 389 of 403 (851379)
04-23-2019 7:59 AM
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Reply to: Message 366 by Faith
04-22-2019 3:50 PM
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Daffynitions make the discussion a farce
You are misusing the terms I use. ... How can that be when I specifically reference your usage -- here it is again:
quote:
Yes, one species or one Kind, that's how I see all those trilobites climbing up the fossil record for the supposed hundreds of millions of years represented there, and it is the sameness of their body structure that enables me to classify them that way. And where did I call it bias to classify other creatures the same way: The problem you have is that you refuse and ignore classifying other creatures the same way:
... the Kind or species is identified by the body structure. ... Then dogs and cats are a "Kind or species (faith usage)" and chimps and humans a "Kind or species (faith usage)" ... where "species (faith usage)" means some original fantasy "species genome" and NOT species as used in biology, science, reality. So funny to watch you wiggle around the actual evidence.
Note that "species (faith usage)" specifically refers to your fantasy definition of species and your inconsistent usage thereof. It appears that you define "species (faith usage)" for trilobites but then not use that definition anywhere else.
You do not get to use my terms to establish your own definitions and impute them to me. And yet they are your definitions, specifically referenced as such. You have caused the discussion to devolve into a farce, by insisting on your attempt to redefine words and then use your daffynition inconsistently.
Definitions, Daffynitions, Delusions, Logic and Critical Thinking. Enjoy
| This message is a reply to: | | | Message 366 by Faith, posted 04-22-2019 3:50 PM | | Faith has not replied |
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RAZD
Member (Idle past 1426 days) Posts: 20714 From: the other end of the sidewalk Joined: 03-14-2004
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Message 401 of 403 (851407)
04-24-2019 6:46 AM
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Reply to: Message 383 by Faith
04-23-2019 12:46 AM
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trilobites spines do complicated things? Now about transitional fossils ...
... They do complicated things with their spines ... Trilobites have spines? Yes, but not like vertebrate spines ...
quote:
Trilobites Identifing different species of trilobite is very hard, but with some guidance it is possible. You can identify a trilobite from the shape of it's shell, the ribs and the spines.
See link for descriptions of 19 species, 7 with no spines. Spine locations and number vary considerably from head to toe on those 12 species with spines, as do the number of ribs. For instance:
quote:
CALYMENE
LOWER SILURIAN TO UPPER DEVONIAN. 430-360 MYA.
Calymene is recognized by it's rounded shell.
4 cm is a decent size for a Calymene.
The calymene trilobites found in Britian usually have 19 segments and those found in America usually have 13 segments.
They have rounded shells but no spines. and CORYNEXOCHIDA
LOWER CAMBRIAN TO UPPER DEVONIAN. 518-360 MYA.
Corynexochida is recognized by it's flat shell.
5 cm is a decent size for a Corynexochida.
They have flat shells and short spines on the Thorax.
They have longer and fewer spines on the Pygidium.
The spines of trilobites have nothing to do with their relative ability to curl up like a sow bug. The spines, when present, can be on the head (Cephalon), thorax, or tail (Pygidium ) and of varying lengths.
As for chimps etc I already said why I consider their body builds to be too different from the human. ... Note the three lobes are longitudinal not transverse. Transverse segments - ribs - vary in number from species to species. This alone makes them more different one to another than are chimps and humans ... if you use the same criteria for classifying the "faith species" (purportedly set by the "faith genome") for trilobites and humans and chimps. And that is the crux of why your classifications are a farce. As for the topic: What would a transitional fossil look like? Without discussing the use or misuse of "species" ...
- A transitional fossil would have some primitive (plesiomorphic) traits/characteristics of an ancestral population
- A transitional fossil would have some derived (altered) traits/characteristics compared to an ancestral population
- A transitional fossil would have fewer derived (altered) characteristics compared to a descendant population
- A transitional fossil will also be in close proximity in both time and geographic location (the temporal/spacial matrix) to ancestral and descendant populations.
ie -- a transitional fossil would be intermediate in form (traits/characteristics) between an ancestral population and a descendant population. Derived traits are traits that have evolved from ancestral traits.
quote:
Transitional forms Fossils or organisms that show the intermediate states between an ancestral form and that of its descendants are referred to as transitional forms. There are numerous examples of transitional forms in the fossil record, providing an abundance of evidence for change over time.
quote:
List of transitional fossils This is a tentative partial list of transitional fossils (fossil remains of groups that exhibits both "primitive" and derived traits). The fossils are listed in series, showing the transition from one group to another, representing significant steps in the evolution of major features in various lineages. These changes often represent major changes in morphology and anatomy, related to mode of life, like the acquisition of feathered wings for an aerial lifestyle in birds, or limbs in the fish/tetrapod transition onto land. Darwin noted that transitional forms could be considered common ancestors, direct ancestors or collateral ancestors of living or extinct groups, but believed that finding actual common or direct ancestors linking different groups was unlikely.[1][2] Collateral ancestors are relatives like cousins in genealogies in which they are not in your direct line of descent but do share a common ancestor (in this case it is a grandparent). This kind of thinking can be extended to groups of life. For instance, the well-known Archaeopteryx is a transitional form between non-avian dinosaurs and birds, but it is not the most recent common ancestor of all birds nor is it a direct ancestor of any species of bird alive today. Rather, it is considered an extinct close evolutionary "cousin" to the direct ancestors. This may not always be the case, though, as some fossil species are proposed to be directly ancestral to others, like how Australopithecus anamensis is most likely to be ancestral to Australopithecus afarensis.[3] Contents
- Nautiloids to ammonoids
- Cephalopods
- Evolution of insects
- Evolution of spiders
- Invertebrates to fish
- Chondrichthyes
- Bony fish
- Fish to tetrapods
- Amphibians to amniotes
- Turtles
- From lizards to snakes
- Lizards
- Pterosaurs
- Archosaurs to dinosaurs
- Dinosauria
- Dinosaurs to birds
- Bird evolution
- Synapsid ("mammal-like reptiles") to mammals
- Evolution of mammals
- Early artiodactylans to whales
- Evolution of sirenians
- Evolution of pinnipeds
- Evolution of the horse
- Human evolution
- See also
- References
- External links
Finally, coming back to trilobites ...
quote:
Trilobite Order Redlichiida Order Redlichiida is divided into two suborders, Olenellina and Redlichiina. ... The Olenellids are restricted to what was Laurentia in the Lower Cambrian, which now includes part of North America. In contrast, the Redlichiina are found in numerous Lower Cambrian locations that were not part of Laurentia. The different stratigraphical ranges are important as they form the basis for the phylenogy of Redlichiida. In fact, Lieberman (2002) has argued that cladistic analysis together with the biogeographic data supports the notion that early trilobite cladogenesis (i.e., the evolutionary splitting) occurred about coincident with the breakup of Pannotia sometime between 600-550 million years ago. Lieberman also conducted cladistic analyses among a group of basal trilobites within the Redlichiina, and the paraphyletic Fallotaspidoids. The group had primitive characteristics, such as the absence of facial sutures allying them with the Olenellina, and other characteristics allying them with the Redlichiina. Shared characteristics supported a phylogenetic position of the fallotaspids as transitional to all or almost all other trilobites except the Olenellina.
Location in the temporal/spacial matrix is established by the "different stratigraphical ranges" and the "biogeographic data" linking the various fossils in time and space. Enjoy Edited by RAZD, : added topic bit
| This message is a reply to: | | | Message 383 by Faith, posted 04-23-2019 12:46 AM | | Faith has not replied |
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